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Evaluate −7c2−7c−9/−7d when c=−2 and d=1. Enter an integer or a fraction.

Evaluate −7c2−7c−9/−7d when c=−2 and d=1. Enter an integer or a fraction.-example-1
User Marek Gregor
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1 Answer

15 votes
15 votes

Replace each variable with their respective values on the given expression to evaluate it:


\begin{gathered} c=-2 \\ d=1 \\ \Rightarrow(-7c^2-7c-9)/(-7d)=(-7(-2)^2-7(-2)-9)/(-7(1)) \end{gathered}

Use the order of operations to simplify the expression. On the numerator, solve for powers first:


(-7(-2)^2-7(-2)-9)/(-7(1))=\frac{-7(4)^{}-7(-2)-9}{-7(1)}

Then, solve for products both in the numerator and denominator:


\frac{-7(4)^{}-7(-2)-9}{-7(1)}=\frac{-28^{}+14-9}{-7}

Then, solve for additions and substractions from left to right:


\begin{gathered} \frac{-28^{}+14-9}{-7}=(-14-9)/(-7) \\ =(-23)/(-7) \end{gathered}

Finally, simplify the fraction using the law of signs:


(-23)/(-7)=(23)/(7)

Therefore, the answer is:


(23)/(7)

User Ramon Poca
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